It is a mould designed to manufacture manholes for water supply or sewerage systems, gas supply lines and communications systems.
Manholes are used at a certain distance in this type of lines to allow (and at the same time restrict) the access to varied elements of the line. In other words, precast manholes are installed in order to perform maintenance and control when needed.
These moulds for manholes are custom designed and made by Moldtech, according to;
- the required dimensions,
- the pipes that have to pass through the manhole
- and the regulations that the manhole has to comply with
Constructively the mould has an inner part which serves as a chassis and casts the interior surfaces of the manhole. The outer sides shape the outer surfaces of the manhole and are attached by hinges to this inside part, that allow the opening and closing of the mould. Both the inner and the outer moulds could have notch boxes or casting imprints to shape the necessary openings for pipes that pass through the manhole.
As additional system to perform the compaction of the concrete, an electrical or pneumatic vibration system can be implemented in the mould. This contributes to release air bubbles, what allows using a formulation of concrete with less proportion of water. This brings an improvement in the time required for the opening of the mould after the hardening of the precast manhole.
Normally the manholes are casted in inverted position, but they tend to be easily turned with the same crane used for their handling and stockpiling.